In Eastern Mysticism, 1♦ is the catch-all bid. It’s what you open when you don’t have a strong hand, a 5-card major, both minors, a preemptive bid, or a 1NT opening.
Not Your Precision 1♦
One of the features distinguishing Eastern Mysticism from Precision is the completely artificial nature of the 1♦ opening. Precision requires at least two diamonds for this opening bid, with 2♣ and 2♦ reserved for average hands with zero or one diamond. The Eastern Mysticism opening doesn’t promise any diamonds at all.
As discussed previously, we made 1♦ completely artificial precisely to avoid Precision-like 2m openings. Precision’s 2♣ makes Responder play a guessing game about a 4-4 major fit at the 2-level, which we found incredibly inconvenient. 2♦ at least describes Opener’s hand thoroughly, but rules out a final 1NT contract.
Speaking of NT, we prefer opening 1♦ with 4-4 in the majors even if balanced and in the appropriate HCP range. This guarantees finding a major fit if one exists. Since Responder to 1NT should pass with as much as 10 HCP (opposite an 11–13 NT opening) when balanced, there’s less chance of being able to use Stayman to find that possible major fit.